Conventionally, in a semiconductor device manufacturing field, a plurality of e.g., 25 substrates such as semiconductor wafers or the like is transferred while being accommodated in a carrier (substrate accommodation container) such as a FOUP (Front Opening Unified Pod) or the like.
An inner space of the carrier such as a FOUP or the like can be sealed and the carrier is transferred in a sealed state between process steps. Meanwhile, as for a substrate processing apparatus for unloading a substrate from the carrier and performing a film formation, an etching or the like on the substrate, there is known a substrate processing apparatus including: a processing module for processing a substrate; and a transfer module having a transfer chamber provided with a loading/unloading port for mounting thereon a carrier and a transfer mechanism installed in the transfer chamber. Moreover, there is also known a substrate processing apparatus including a purge mechanism for supplying an inert gas into a FOUP mounted on a loading/unloading port and replacing the atmosphere in the FOUP (e.g., Japanese Patent Application Publication No. 2003-45933 and its corresponding U.S. Patent Application Publication No. 2003-031537).
Besides, there is suggested a substrate storage technique for accommodating processed substrates in a storage for the purpose of separating unprocessed substrates from the processed substrates and removing deposits so that the unprocessed substrates are prevented from being adversely affected by the deposits such as by-products or the like adhered onto substrates during processing of the substrates.
However, in case of the above-described conventional substrate processing apparatus having the purge mechanism for purging the FOUP with the inert gas, the atmosphere in the FOUP is replaced by purging the FOUP with the inert gas or the like while a front opening of the FOUP is fully opened during processing of a plurality (e.g., 25) of substrates (one lot) accommodated in the FOUP, so that the atmosphere can be introduced into the FOUP through the front opening. Hence, a first processed substrate of a lot is exposed to the atmosphere for a long period of time until the last processed substrate of the lot returns to the FOUP and may undesirably react with moisture in the atmosphere or the like.
Also in the storage technique for accommodating processed substrates in a storage, the processed substrates are exposed to the atmosphere and may undesirably react with moisture in the atmosphere or the like.
For example, when a target layer is plasma-etched by using fluorine-containing gas so that copper wiring formed under the etching target layer is exposed, hydrofluoric acid is generated from a reaction between by-products containing fluorine and moisture in the atmosphere, which may lead to corrosion of the copper wiring.